Answer:
Both of those are functions.
Explanation:
is a parabola that opens up.
Any upward or downward parabola is a function because they pass the vertical line test.
![x=\pm √(1-y){/tex]</p><p>Square both sides:</p><p>[tex]x^2=1-y](https://img.qammunity.org/2020/formulas/mathematics/middle-school/uac50zcppbf06p2xnj0y0yhvpckgrjc581.png)
Subtract 1 on both sides:
![x^2-1=-y](https://img.qammunity.org/2020/formulas/mathematics/middle-school/fseji4ifhtwuope8d4fbi1x5unw25h5xkb.png)
Multiply both sides by -1:
![-x^2+1=y](https://img.qammunity.org/2020/formulas/mathematics/middle-school/mzk5rad9x2dkc7zvn76tuni114asxochd3.png)
So this is a another parabola and it is faced down. So this is also a function.
wit
willl always be a parabola.
If
then it is open up.
If
then it is open down.
Upwards and downward parabolas will always be functions.
are also parabolas but these open to the left or right. These will not be functions because they will not pass the vertical line test.